1. Field of the Invention
The present invention relates generally to heat exchangers and, more specifically, to an evaporator and method of making same with stamped end tanks and extruded tubes for an air conditioning system in a motor vehicle.
2. Description of the Related Art
It is known to provide a heat exchanger such as an evaporator for an air conditioning system in a motor vehicle. The evaporator typically receives a fluid such as a refrigerant. The evaporator normally includes a plurality of flow passages, which may, for example, be constructed from flat plates or extruded, tubes extending between opposite manifolds or end tanks. The evaporator also includes a plurality of cooling fins disposed between the flow passages. Evaporators are generally much thicker than condensers, and thus require as manifolds or end tanks that may be as wide or wider than fifty-five millimeters. One type of evaporator, often referred to as an extruded tube evaporator, includes a plurality of extruded tubes extending between the end tanks to direct the refrigerant through a plurality of flow paths. However, the end tanks typically used for extruded tube condensers do not have the required strength due to the vastly increased surface area and thus force present in such a wide heat exchanger. Another type of evaporator, often referred to as a plate-fin evaporator, includes a plurality of plates extending between the end tanks to direct the refrigerant through a plurality of flow paths. The end tanks are stamped by using a drawn-cup process.
Therefore, it is desirable to provide an evaporator with stamped end tanks and extruded tubes. It is also desirable to combine the benefits of stamped plate-fin evaporators and extruded tube heat exchangers.
Accordingly, the present invention is an evaporator including a first end tank, a second end tank spaced from and opposing the first end tank, and a plurality of extruded fluid carrying tubes extending between and in fluid communication with the first end tank and the second end tank. The first end tank and the second end tank are formed as stampings.
One advantage of the present invention is that a new evaporator and method of making same are provided for an air conditioning system of a motor vehicle. Another advantage of the present invention is that the evaporator has extruded tubes and stamped end tanks. Yet another advantage of the present invention is that the evaporator combines the benefits of stamped plate-fin evaporators and extruded tube heat exchangers. Still another advantage of the present invention is that the evaporator uses a drawn-cup manifold, stamped such that, when assembled, accept extruded tubes for passage of refrigerant. A further advantage of the present invention is that the evaporator has the increased heat transfer surface area of the extruded tube combined with the strength and manufacturing flexibility of a drawn-cup manifold.
Other features and advantages of the present invention will be readily appreciated, as the same becomes better understood, after reading the subsequent description taken in conjunction with the accompanying drawings.